1. Field of the Invention
The present invention relates to a pushbutton-operated waveband or station selector, and more particularly to an improved arrangement of the clutch mechanism and manual-operating tuning shafts thereof.
2. Description of the Prior Art
The pushbutton-operated waveband or station selector is a device in which a crank is provided through a predetermined angle by means of one of plural station selecting pushbuttons to insert or extract a tuning core into or from a tuning coil for the purpose of selecting a desired station. Further, the waveband or station selector is provided with a manual tuning knob in addition to the above-mentioned waveband or station selecting pushbuttons. By turning the tuning knob, it is possible to select other stations than selected by means of the pushbutton, to make a fine adjustment at time of the waveband or station selection, or to set a carrier frequency for each of the pushbuttons. If the pivoting crank is left as coupled with the tuning knob during the operation of the pushbuttons, the load will be too large to smoothly operate the pushbuttons; to avoid this, there is provided a clutch mechanism between the crank and the tuning knob. This clutch is so designed that it is disconnected when any one of the pushbuttons is operated and that only the crank is pivoted without turning the tuning knob, thus reducing the load to the pushbuttons.
The conventional clutch mechanism and tuning knob interlocked with such clutch mechanism are so arranged that they protrude out of the frame side panel of the pushbutton-operated waveband or station selector. Specifically, a plurality of pushbuttons is disposed on the frontal side of the selector while the cllutch mechanism and tuning knob are arranged on the lateral side thereof. However, as the pushbutton-operated waveband or station selector has recently been designed compact, it has been proposed to reduce the the width of the apparatus as a whole. In this case, since it is impossible to make the width of the selector body smaller than a certain extent because of the number of tuning coils or of the width of the operating pushbuttons, the clutch mechanism and tuning knob which are disposed outside the selector frame must be reduced as much as possible. However, the conventional pushbutton-operated waveband or station selectors are designed under the assumption that the clutch mechanism and manual tuning knob are located outside the selector frame; therefore, however compact the components of the selector are designed, the clutch mechanism and tuning knob are so arranged as to protrude out of the frame. The reduction of the width of the selector as a whole is thus limited.